Otis technology Tactical replacement brushes are high quality bore brushes that scour all offending dirt and grime from the interior of your weapon. The superior construction of these cleaning tools set them on a plane above the rest. Competitive features like a cold-welded stem, tighter bristle pattern, and a precision thread make the difference between a bargain bore brush and one that will serve you for years to come. Otis technology has made these bore brushes corrosion-resistant with their trademarked tufcor proprietary core wire, and the Otis Tech Tactical replacement brush can be used with all cleaning chemicals without damage..